Some Members of Congress get their jobs the old-fashioned way: by apprenticing for them.

Since World War II, the number of seats in Congress occupied by former Congressional staffers has dramatically increased, with many in the positions once held by their former bosses.

In the 112th Congress alone, 81 Members have previously worked as staffers, according to CQ Roll Call’s Politics in America 2012. A survey by Roll Call found that 32 inherited the seats of the Members they once worked for, two more than in the 111th Congress. The roster includes four House freshmen and one first-term Senator.

At least one former staffer — Hawaii Democrat Esther Kia’aina — is vying for a seat in next year’s elections.

Staffers are uniquely prepared and well-positioned to run for Congress for several reasons, according to Paul Herrnson, director of the Center for American Politics and Citizenship at the University of Maryland, College Park. They have immersed themselves in politics for years, which teaches them about constituent issues and gives them valuable connections to lawmakers, staffers, party leaders, consultants and lobbyists. They also learn how to raise money and run successful campaigns.

“It’s who they are,” Herrnson said.

Staffers have the upper hand when a Member retires after years of loyal service and high approval ratings, because they can offer voters the promise of continuity and a smooth transition.

They sometimes struggle, however, when it comes to facing off against local officials with greater name recognition at home, said Christopher Deering, a politics professor at George Washington University. These staffers-turned-candidates may have difficulty shedding the label of the “Washington insider,” especially in times when the Capitol has fallen out of favor.

“The disadvantage of working in Washington is that they’re not always on the ground back home,” Deering said. “But normally, they’re from their bosses’ districts,” which would give them an advantage if they seek office there, he said.

Before World War II, it was more unusual for staffers to work their way up to elected office because there were only a few personal aides on Capitol Hill.

The Legislative Reorganization Act of 1946 allowed Members to hire larger staffs. With more staffers getting to know the ins and outs of Congressional life, it became more likely that some of them would want to run for office themselves.

In a 1994 study, Herrnson discovered that from 1978 to 1988, 2.6 percent of non-incumbent candidates came from a strictly staffing background. While it may seem like a small group, Herrnson’s numbers also showed that candidates who ran for office with that background were more likely to beat their opponents in primary and general elections — even against previously elected officials.

Rep. Frank Guinta is one example of the staffer-to-lawmaker success story. The New Hampshire Republican ran in 2010 on his record of public service as the former mayor of Manchester. But he also leveraged his two-year stint as a district aide for Rep. Jeb Bradley (R), who held the same seat from 2003 to 2007.

“Certainly I had a unique perspective of the 1st Congressional district that you don’t get unless you’re serving it in that capacity,” said Guinta, who described his geographically diverse district as one where constituents place a high premium on in-person interactions with local officials.

“Individuals there expect to have relationships with Members of Congress,” he said. “It helped that I knew a lot of people throughout the district before the campaign began.”

Rep. Bill Huizenga (R) capitalized on his connections to Michigan’s 2nd district in his successful 2010 campaign to succeed retiring Rep. Pete Hoekstra (R). Huizenga was Hoekstra’s home-based policy director for six years.

“My job was literally to be his eyes and ears,” Huizenga said. “And it was a huge advantage in the campaign because we were going into some of these small towns, and my opponents had never been there before, but I had. ... I knew asparagus was important, I knew particular manufacturing issues were important. ... I knew them.”

Kia’aina hopes her long history with Hawaii’s 2nd district will also resonate with voters. With Election Day more than a year away, the former Hill staffer is pursuing a seat that has been held by two of her former bosses.

Kia’aina, who is currently chief advocate for the Office of Hawaiian Affairs, is campaigning to succeed Rep. Mazie Hirono (D), who has entered the race for the seat held by retiring Sen. Daniel Akaka (D-Hawaii).

Kia’aina lived and worked in Washington, D.C., for more than two decades before returning to Hawaii. Akaka held the 2nd district seat for 13 years before being appointed to the Senate, and Kia’aina was his legislative assistant during his first nine years as a Senator. She was also chief of staff for Rep. Ed Case (D), who represented the district from 2002 to 2007.

Kia’aina believes her level of experience will serve her well. Like Guinta and Huizenga, she emphasizes her knowledge about the diverse district and her insights into the needs of her constituents.

But she also knows how she would fare in a Capitol Hill office after spending so much time there.

“I have a good appreciation for what is necessary on Day 1, and not only organizing an office and assembling a good staff,” she said. “I know how to hit the ground running.”